A man, wearing a costume that represents the Amazon rain forest, demonstrates during the People's Summit at Rio+20 for Social and Environmental Justice in Rio de Janeiro June 17, 2012. The People's Summit at Rio+20 for Social and Environmental Justice is a parallel event of the Rio+20 United Nations sustainable development summit that will be held from June 20 to 22. REUTERS/Ricardo Moraes (BRAZIL - Tags: ENVIRONMENT POLITICS SOCIETY CIVIL UNREST)

A man, wearing a costume that represents the Amazon rain forest, demonstrates during the People's Summit at Rio+20 for Social and Environmental Justice in Rio de Janeiro June 17, 2012. The People's Summit at Rio+20 for Social and Environmental Justice is a parallel event of the Rio+20 United Nations sustainable development summit that will be held from June 20 to 22. REUTERS/Ricardo Moraes (BRAZIL - Tags: ENVIRONMENT POLITICS SOCIETY CIVIL UNREST)

A model depicting the Statue of Liberty is seen during the People's Summit at Rio+20 for Social and Environmental Justice in Rio de Janeiro June 17, 2012. The People's Summit at Rio+20 for Social and Environmental Justice is a parallel event of the Rio+20 United Nations sustainable development summit that will be held from June 20 to 22. REUTERS/Ricardo Moraes (BRAZIL - Tags: ENVIRONMENT POLITICS SOCIETY CIVIL UNREST)

A model depicting the Statue of Liberty is seen during the People's Summit at Rio+20 for Social and Environmental Justice in Rio de Janeiro June 17, 2012. The People's Summit at Rio+20 for Social and Environmental Justice is a parallel event of the Rio+20 United Nations sustainable development summit that will be held from June 20 to 22. REUTERS/Ricardo Moraes (BRAZIL - Tags: ENVIRONMENT POLITICS SOCIETY CIVIL UNREST)

Activists hold up a banner depicting a $1 trillion note dripping with oil on Copacana beach June 17, 2012, ahead of the Rio+20 United Nations sustainable development summit. According to the organizers, the activists were calling on Rio+20 leaders to deliver a new plan to save the planet by shifting the nearly $1 trillion spent each year on fossil fuel subsidies to renewable energy and sustainable development. The Rio+20 United Nations sustainable development summit that will be held from June 20 to 22. REUTERS/Ana Carolina Fernandes (BRAZIL - Tags: ENVIRONMENT ENERGY CIVIL UNREST POLITICS)

Activists hold up a banner depicting a $1 trillion note dripping with oil on Copacana beach June 17, 2012, ahead of the Rio+20 United Nations sustainable development summit. According to the organizers, the activists were calling on Rio+20 leaders to deliver a new plan to save the planet by shifting the nearly $1 trillion spent each year on fossil fuel subsidies to renewable energy and sustainable development. The Rio+20 United Nations sustainable development summit that will be held from June 20 to 22. REUTERS/Ana Carolina Fernandes (BRAZIL - Tags: ENVIRONMENT ENERGY CIVIL UNREST POLITICS)

Activists hold up a banner depicting a $1 trillion note dripping with oil on Copacana beach June 17, 2012, ahead of the Rio+20 United Nations sustainable development summit. According to the organizers, the activists were calling on Rio+20 leaders to deliver a new plan to save the planet by shifting the nearly $1 trillion spent each year on fossil fuel subsidies to renewable energy and sustainable development. The Rio+20 United Nations sustainable development summit that will be held from June 20 to 22. REUTERS/Ana Carolina Fernandes (BRAZIL - Tags: ENVIRONMENT ENERGY CIVIL UNREST POLITICS)

Activists hold up a banner depicting a $1 trillion note dripping with oil on Copacana beach June 17, 2012, ahead of the Rio+20 United Nations sustainable development summit. According to the organizers, the activists were calling on Rio+20 leaders to deliver a new plan to save the planet by shifting the nearly $1 trillion spent each year on fossil fuel subsidies to renewable energy and sustainable development. The Rio+20 United Nations sustainable development summit that will be held from June 20 to 22. REUTERS/Ana Carolina Fernandes (BRAZIL - Tags: ENVIRONMENT ENERGY CIVIL UNREST POLITICS)

A woman holds up a placard as members of different religions protest against Iranian President Mahmoud Ahmadinejad in the "Rio +20" United Nations Conference on Sustainable Development, on Ipanema beach in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY)

A Brazilian navy ship patrols near Arpoador beach ahead of the "Rio +20" United Nations Conference on Sustainable Development in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY MILITARY)

A Brazilian navy ship patrols near Ipanema beach ahead of the "Rio +20" United Nations Conference on Sustainable Development in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY MILITARY TPX IMAGES OF THE DAY)

A Brazilian navy ship patrols near Ipanema beach ahead of the "Rio +20" United Nations Conference on Sustainable Development in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY MILITARY)

A Brazilian navy ship patrols near Ipanema beach ahead of the "Rio +20" United Nations Conference on Sustainable Development in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY MILITARY)

Brazilian army soldiers patrol on Ipanema beach ahead of the "Rio +20" United Nations Conference on Sustainable Development in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY MILITARY)

A baby is seen below a T-shirt that reads: "No Ahmadinejad in Rio" as members of different religions protest against Iranian President Mahmoud Ahmadinejad in the "Rio +20" United Nations Conference on Sustainable Development, on Ipanema beach in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY)

Members of different religions protest against Iranian President Mahmoud Ahmadinejad in the "Rio +20" United Nations Conference on Sustainable Development, on Ipanema beach in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY)

Members of different religions protest against Iranian President Mahmoud Ahmadinejad in the "Rio +20" United Nations Conference on Sustainable Development, on Ipanema beach in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY)

Members of different religions protest against Iranian President Mahmoud Ahmadinejad in the "Rio +20" United Nations Conference on Sustainable Development, on Ipanema beach in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY)

Members of different religions protest against Iranian President Mahmoud Ahmadinejad in the "Rio +20" United Nations Conference on Sustainable Development, on Ipanema beach in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY)

Demonstrators hold a gay flag as members of different religions protest against Iranian President Mahmoud Ahmadinejad in the "Rio +20" United Nations Conference on Sustainable Development, on Ipanema beach in Rio de Janeiro June 17, 2012. The "Rio +20" United Nations Conference on Sustainable Development will be held from June 20 to June 22. REUTERS/Sergio Moraes (BRAZIL - Tags: ENVIRONMENT CIVIL UNREST POLITICS SOCIETY)